Pneumatic clamp

ABSTRACT

A fitting for providing a connection between a tank of compressed gas and a diving mask including a body provided with an arm arranged to loosely embrace the outlet valve of the tank of compressed air. A piston is slidably mounted with respect to the bore and includes an inlet disposed to register with the outlet valve of the compressed air tank and an outlet adapted for connection to the diving mask. A filter is disposed within the inlet. A spring urges the piston and the body toward a position in which the arm clamps about the outlet valve of the compressed air tank and the inlet of the piston receives air from the outlet valve. A passage bypassing the filter and connected with the inlet directs air to an area of the piston to aid the spring in producing a tight engagement between the inlet provided in the piston and the outlet valve.

United States Patent Dockery Feb. 1, 1972 [54] PNEUMATIC CLAMP [72] Inventor: Denzel J. Docket-y, 6-4142 Fenton Road,

Flint, Mich. 48507 [22] Filed: July 29, I970 [21] Appl.No.: $9,119

Related US. Application Data [63] Continuation-impart of Ser. No. 710,856, Mar. 4, 1968, abandoned, which is a continuation-in-part of Ser. No. 673,662, Oct. 9, 1971, Pat. No. 3,434,994.

FOREIGN PATENTS OR APPLICATIONS 931,968 7/1963 Great Britain 1 37/63 R Primary Examiner-Henry T. Klinksiek AttorneyHauke, Gifford and Patalidis [5 7] ABSTRACT A fitting for providing a connection between a tank of compressed gas and a diving mask including a body provided with an arm arranged to loosely embrace the outlet valve of the tank of compressed air. A piston is slidably mounted with respect to the bore and includes an inlet disposed to register with the outlet valve of the compressed air tank and an outlet adapted for connection to the diving mask. A filter is disposed within the inlet. A spring urges the piston and the body toward a position in which the arm clamps about the outlet valve of the compressed air tank and the inlet of the piston receives air from the outlet valve. A passage bypassing the filter and connected with the inlet directs air to an area of the piston to aid the spring in producing a tight engagement between the inlet provided in the piston and the outlet valve.

13 Claims, 4 Drawing Figures saw 1 or g INVENTOR. DENZEL J. DOCKERY I ATTORNEYS PATENTED FEB 1972 8538.675

sumanrz INVENTOR DENZEL J. DOCKERY BY We; @W fl/JW ATTORNEYS PNEUMATIC CLAMP This application is a continuation-in-part of my application Ser. No. 710,856, filed Mar, 4, 1968, now abandoned, which in turn was a continuation-in-part of my application Ser. No. 673,662, filed Oct. 9, 1971 and now U.S. Pat. No. 3,434,494.

BACKGROUND OF THE INVENTION I. Field of the Invention The present invention relates to fittings for providing a connection with tanks of pressurized air and the like and more particularly to such a device utilizing tank pressure to aid in providing a clamping engagement with the tank.

ll. Description of the Prior Art Heretofore fittings for making a connection with pressurized tanks have generally included a clamp of some sort utilizing some type of mechanical action to make the required fluidtight connection. Such clamps have generally used a threaded member and therefore have required considerable time and strength to connect and disconnect with respect to the tank.

In a number of situations time is very valuable and there has been a need for a clamping device which can be quickly connected and disconnected. One such situation is underwater diving where it may be necessary to change tanks while beneath the surface of the water. When this is necessary it is important that the disconnection of the old tank and new connection be made with a minimum of time and effort.

SUMMARY OF THE PRESENT INVENTION The present invention provides a device for easy connection with a tank of pressurized fluid such as the tank of compressed oxygen used by underwater divers. The device includes a spring-actuated piston which provides the initial connection and clamping action between the device and the outlet valve of the tank. Once the connection has been established, pressure from the tank is directed behind the piston to increase the clamping force and thereby insure a fluidtight connection.

U.S. Pat. No. 3,430,494 issued to me Mar. 4, I969, discloses and claims a pneumatic clamp similar to the device herein disclosed but intended primarily to provide a means for connecting a pressure gage to the tank. The connection is made by a piston urged by fiuid pressure from the tank into engagement with the outlet valve and against the force of a spring. Disconnection is made by first shutting off fiow from the tank and then opening a valve to relieve pressure from behind the piston. Once the pressure is relieved, the spring then urges the piston away from the outlet valve of the tank to permit disengagement.

To utilizethis type of clamp to connect breathing apparatus to a tank of compressed air produces a serious problem. Once the air from the tank has been exhausted the clamp will be disconnected by the spring and this can occur while deep underwater.

A copending application of mine discloses a device similar to the one disclosed in my aforementioned patent but in which this problem is overcome by providing a construction in which a spring urges the device toward the engaged position. Further, the piston is mounted in a stationary position and the spring and the fluid pressure urge the arm toward the piston to securely clamp the outlet valve of the tank therebetween. The connection between the tank and the chamber for urging the piston into engagement is located on the outlet side of the piston and thus on the outlet side of the filter. While this valve construction has been satisfactory for the most part one serious problem has occasionally occurred. When the filter becomes clogged the air inhaled by the diver will be drawn at least in part from the chamber and thus the tank may become disconnected. This could, of course, produce a serious accident.

The present device provides a solution to this problem by connecting the chamber to tank pressure by a passage extending through the piston from the inlet side of the filter. Thus as long as there is tank pressure the chamber will remain pressurized and the clamp will remain securely locked to the tank. With this construction it is not possible to accidentally deplete the chamber.

Fittings somewhat similar in construction to the fitting herein disclosed have been previously utilized as lubrication nozzles. US. Pat. No. 1,960,529 issued to Adiel Dodge on May 29, 1934, is an example of these types of fittings and discloses a lubrication nozzle in which pressurized lubricant is utilized to aid in clamping the nozzle to a lubrication fitting. There are, however, important distinctions between lubrication nozzles of this type and the fitting of the present invention. First the flow in these devices is in the opposite direction. In diving apparatus the flow of air is from the valve on the tank through the fitting and to the breathing apparatus. In lubrication nozzles the lubricant under pressure is supplied to the device upon which the nozzle is clamped. Also there is no filter in lubrication nozzles and the problem of depleting the piston chamber when the filter becomes clogged is therefore nonexistent. Accidental disconnection of lubrication nozzles is of course not nearly as serious a problem as is accidental disconnection of diving apparatus.

BRIEF DESCRIPTION OF THE DRAWING The description of a preferred embodiment of the present invention makes reference to the following drawings in which like reference characters refer to like parts throughout the several views and in which,

FIG. 1 is a perspective view illustrating the fitting of the present invention as a part of a preferred assembly;

F IG, 2 is an exploded perspective view of the preferred fitting of the present invention;

FIG. 3 is a longitudinal cross-sectional view of the preferred fitting of the present invention, and

FIG. 4 is a view partly in section of an assembly utilizing two of the preferred fittings of the present invention.

DESCRIPTION OF A PREFERRED EMBODIMENT Now referring to the drawings for a more detailed description of the present invention an assembly is shown in FIG. 1 to illustrate one preferred use of the fitting of the present invention. The assembly is for underwater diving and the like and preferably comprises a conventional pressure regulator assembly including a first stage regulator 10, a hose l2 and a second stage regulator 14.

A fitting generally indicated at 16 is connected with the first stage regulator 10 and clamps to the outlet valve 17 of a tank 18 of compressed air.

As can best be seen in FIG. 3 the fitting 16 preferably comprises a substantially cylindrical body 20, preferably formed of brass or other noncorrosive metal and provided with a cylindrical bore 22 extending from an open end to a wall 24. A reduced diameter bore 26 extends through the wall 24 coaxially with the bore 22.

The bores 22 and 26 provide the means for axially slidably receiving a piston 28 having a reduced diameter section 30 extending through the bore 26 and preferably provided at its outer end with external threads 32. The piston 28 carries an O-ring seal 34 which in combination with an O-ring seal 36 carried by the wall 24 seals a chamber 38 between the enlarged portion of the piston 28 and the wall 24. A spring 40 is carried in the chamber 38 and between the wall 24 and the piston 28 and thus urges the piston 28 and the body 20 toward a separated position.

The piston 28 is provided with a forwardly extending portion defining an annular lip 42 forming an inlet 44 for engaging the outlet valve 17 of the tank 18 in a manner which will become more apparent as the description proceeds. A central longitudinal bore 46 is drilled through the piston 28 to provide communication between the inlet 44 and the end of the reduced portion 30. A passage 48 connects the inlet 44 and the chamber 38 from the inlet side of a filter disc 50 which is mounted in the inlet 44 by means of a snapring 52 and a resilient O-ring member 54,

A clamp member preferably comprises a hollow cylindrical base 56 formed with internal threads 58 and the body 20 is provided with external threads 60 for receiving the base 56. An arm 62 has each end formed integrally with the base 56 and forms a crosspiece 64 spaced from and extending substantially normal to the inlet 44.

As the invention has thus far been described it is apparent that expansion of the chamber 38 as caused by the spring 40 and an increase of pressure within the chamber 38 will cause a relative sliding movement between the body 20 and the piston 28. This in turn will decrease the distance between the crosspiece 64 and the inlet end of the piston 28. Thus, in the preferred use of the device illustrated in FIG. 1 the threaded end 32 of the piston 28 is mounted to the first stage regulator 10 of a conventional pressure regulator assembly. The outlet 15 valve 17 of the tank 18 is positioned intermediate the inlet end of the piston 28 and crosspiece 64 so that the arm 62 embraces the outlet valve 17 and the inlet 44 is disposed adjacent the outlet of the outlet valve 17.

The spring 40 will urge the piston 28 and the crosspiece 64 toward one another so that with the outlet valve 17 in the proper position and with the valve 19 of the outlet valve 17 opened compressed air will enter the inlet 44 and pass through the filter disc 50 to the outlet end 32 of the piston 28 and to the pressure regulator assembly. Compressed air will also be directed from the inlet side of the filter disc 50 through the passage 48 to the chamber 38 to securely clamp the fitting 16 to the tank 18.

When it is desired to disengage the fitting 16 from the tank 18 the valve 19 is closed and pressure is exhausted from the chamber 38 by relieving pressure through the second stage regulator 14. This will ordinarily be done by the diver taking a deep breath after closing the valve 19 to thereby exhaust the system. Once the pressure is relieved from the chamber 38 the fitting 16 can be disengaged by grasping the first stage regulator l and the arm 62 and pulling in opposite directions to separate the piston 28 and the crosspiece 64.

By providing the passage 48 connected with the chamber 38 and bypassing the filter disc 50 the chamber 38 will remain pressurized even if the filter disc becomes clogged. There is no danger then in the diver depleting the chamber 38 by inhaling and thereby producing a disconnection between the diving mask and the tank.

F IG. 4 illustrates another preferred assembly of the present invention in which two fittings 16 are connected on opposite sides of the first stage regulator 10 of a pressure regulator assembly. To permit this connection an extension 66 is formed with an internally threaded portion 68 adapted to be received by the threaded exterior end 32 of the piston 28 and is in turn provided with an externally threaded end 70 adapted to be received by the first-stage pressure regulator 10. A central through bore 72 is provided in the extension 66.

The assembly shown in FIG. 4 is especially useful in a twotank assembly. With tanks like those described above each of the fittings 16 is clamped to the outlet valve of one of the tanks substantially in the manner described above. In this way a single first-stage regulator can be used for a dual tank assembly rather than the two necessary in usual constructions. Further a single tank assembly can be readily converted to a dual tank assembly merely by connecting another fitting and the extension 66 in place. These advantages of the assembly shown in FIG. 4 are, of course, in addition to the advantages inherent in the construction of the fitting 16 itself as described above.

it is also apparent that although I have described but several preferred uses of my fitting many other uses will be readily apparent to one skilled in the art to which the invention pertains.

Having thus described my invention, 1 claim:

1. A fitting for connection to an outlet valve of a container of pressurized fluid, said fitting comprising,

a body member having a hollow cylinder formed therein,

a piston axially slidably mounted in said cylinder and being provided with an inlet adapted at one position of said piston to engage the outlet valve of said container of pressurized fluid and at another position to disengage from said outlet valve,

outlet means connecting with said inlet and adapted for connection to means for receiving the fluid from said container, filter means disposed intermediate said inlet and said outlet means,

means forming a chamber on one side of said piston to move said piston toward said outlet valve engaging position when said chamber is pressurized, and means connecting said chamber to said inlet on the inlet side of said filter means to thereby connect said outlet valve of said container to said chamber.

2. The fitting as defined in claim 1 and including an arm member carried by said body and including a crossmember spaced from the inlet end of said piston and operative upon movement of said piston toward said outlet valve engaging position to engage the opposite side of said outlet valve to clamp said device to said container.

3. The fitting as defined in claim 2 and including means for mounting said piston in a stationary position whereby said arm member and body axially slidably move toward and away from said piston.

4. The fitting as defined in claim 1 and including,

a second body member and a piston axially slidably mounted within said second body member,

an arm and a crossmember carried by said second body member with said second body member piston and crossmember cooperating to engage to and disengage from an inlet valve member of a second container of pressurized means fluidly connecting said body members.

5. The fitting as defined in claim 4 and in which said lastmentioned means includes a pressure-regulating means.

6. A fitting for connection to an outlet valve of a container 3 of pressurized fluid said fitting comprising,

a body member having a hollow cylinder formed therein and open to one end and a reduced diameter bore extending into said hollow cylinder from the opposite end,

a piston axially slidably mounted in said cylinder and having a reduced diameter section extending through said bore,

said piston being provided with inlet means formed at the end of said piston adjacent the open end of said body member, outlet means on the end of said reduced diameter section exteriorly of said body member, and filter means disposed intermediate said inlet means and said outlet means,

clamping means carried by said body member,

said piston and said clamping means being movable intermediate a position in which the outlet valve of said container is clamped intermediate said piston and said clamping means and said inlet is received by said outlet valve and a position in which said outlet valve is disengaged from between said piston on said clamping means, and

means for selectively moving said piston and said clamping means intermediate said positions including means directing fluid pressure from said inlet on the inlet side of said filter means to an area on one side of said piston to move said clamping means and said piston relative to each other and toward said outlet valve engaging position.

7. The fitting as defined in claim 6 and including means biasing said clamping means and said piston toward said outlet valve engaging means.

8. The fitting as defined in claim 6 and in which said clamping means includes an arm member carried by said body and including a crossmember spaced from the inlet end of said piston and operative upon fluid being directed to the end of said piston opposite said inlet end to move relative to said piston toward a position engaging the side of said outlet valve opposite said inlet end of said piston to clamp said device to s said container.

9. The fitting as defined in claim 6 and including a pressureregulating means connected to said outlet end of said piston.

10. The fitting as defined in claim 9 and including a second device having a body, a piston axially slidably mounted within 75 said body, clamping means movable relative to said piston and operable at one relative position of said piston and said clamping means to clampingly engage the outlet valve of a second container of pressurized fluid, said last-mentioned piston having inlet means received by said outlet valve and outlet means, and means connecting said outlet means and said pressureregulating means.

11. A clamping and fluid transmission fitting for connection to an outlet valve of a container of pressurized fluid, said valve comprising a stem extending from said container, and said fitting comprising:

a body member including a closed loop portion and having a cylinder formed integral therewith;

a piston reciprocably mounted in said cylinder provided with an inlet adapted at one position of said piston to communicate with said outlet valve of said container of pressurized fluid when said loop portion is engaged over said stem and at another position to disengage from said outlet valve, said closed loop portion having spaced substantially parallel arm members carried by said body member and including a straight crossmember spaced from the inlet end of said piston and extending between said arm members, said crossmember being operative upon movement of said piston toward said outlet valve engaging position to engage the opposite side of said stem of said outlet valve to clamp said device to said container;

outlet means connected to said inlet and adapted for connection to means for receiving pressurized fluid from said container;

filter means intermediate said inlet and said outlet means,

means for selectively moving said piston between said positions including means normally biasing said piston and said loop portion toward said stem of said outlet valve for clamping engagement therewith and means for receiving fluid from said outlet valve upon communication between said inlet of said piston and said outlet valve directed to an area behind said piston to augment the biasing movement of said piston and said loop portion towards said clamping engagement around said stern, said last-mentioned means comprising a chamber formed on one side of said piston, a passage through said piston connecting said inlet on the inlet side of said filter means with said chamber.

12. A clamping and fluid transmission fitting for connection to the outlet valves of a pair of containers of pressurized fluid, each of said valves comprising a stern extending from one of said containers, and said fitting comprising a pair of clamps:

each of said clamps comprising:

a body member having a closed loop portion and a cylinder formed integral therewith;

a piston reciprocably mounted in said cylinder provided with an inlet adapted at one position of said piston to communicate with the outlet valve of one of said containers of pressurized fluid when said loop portion is engaged over the stem of said outlet valve and at another position to disengage from said outlet valve;

means for selectively moving said piston between said positions including means normally biasing said piston and said loop portion toward one of the stems of said outlet valves for clamping engagement therewith and means receiving fluid from said outlet valve upon communication between said inlet of said piston and said outlet valve and directing the fluid to an area behind said piston to augment the biasing movement of said piston and said loop portion towards said clamping engagement around said stern;

outlet means connected to a fluid actuating device for receiving pressurized fluid from said container,

a filter means intermediate said inlet and said outlet means and said directing means including a passage through said piston connecting said area behind said piston with the inlet side of said filter means.

13. The fitting as defined in claim 12. wherein said connecting means includes a tubular extension extendin between the outlet means of one of said clamps and said uid actuating device, the outlet means of the other ofsaid clamps being connected directly into said fluid actuating device. 

1. A fitting for connection to an outlet valve of a container of pressurized fluid, said fitting comprising, a body member having a hollow cylinder formed therein, a piston axially slidably mounted in said cylinder and being provided with an inlet adapted at one position of said piston to engage the outlet valve of said container of pressurized fluid and at another position to disengage from said outlet valve, outlet means connecting with said inlet and adapted for connection to means for receiving the fluid from said container, filter means disposed intermediate said inlet and said outlet means, means forming a chamber on one side of said piston to move said piston toward said outlet valve engaging position when said chamber is pressurized, and means connecting said chamber to said inlet on the inlet side of said filter means to thereby connect said outlet valve of said container to said chamber.
 2. The fitting as defined in claim 1 and including an arm member carried by said body and including a crossmember spaced from the inlet end of said piston and operative upon movement of said piston toward said outlet valve engaging position to engage the opposite side of said outlet valve to clamp said device to said container.
 3. The fitting as defined in claim 2 and including means for mounting said piston in a stationary position whereby said arm member and body axially slidably move toward and away from said piston.
 4. The fitting as defined in claim 1 and including, a second body member and a piston axially slidably mounted within said second body member, an arm and a crossmember carried by said second body member with said second body member piston and crossmember cooperating to engage to and disengage from an inlet valve member of a second container of pressurized fluid, and means fluidly connecting said body members.
 5. The fitting as defined in claim 4 and in which said last-mentioned means includes a pressure-regulating means.
 6. A fitting for connection to an outlet valve of a container of pressurized fluid said fitting comprising, a body member having a hollow cylinder formed therein and open to one end and a reduced diameter bore extending into said hollow cylinder from the opposite end, a piston axially slidably mounted in said cylinder and having a reduced diameter section extending through said bore, said piston being provided with inlet means formed at the end of said piston adjacent the open end of said body member, outlet means on the end of said reduced diameter section exteriorly of said body member, and filter means disposed intermediate said inlet means and said outlet Means, clamping means carried by said body member, said piston and said clamping means being movable intermediate a position in which the outlet valve of said container is clamped intermediate said piston and said clamping means and said inlet is received by said outlet valve and a position in which said outlet valve is disengaged from between said piston on said clamping means, and means for selectively moving said piston and said clamping means intermediate said positions including means directing fluid pressure from said inlet on the inlet side of said filter means to an area on one side of said piston to move said clamping means and said piston relative to each other and toward said outlet valve engaging position.
 7. The fitting as defined in claim 6 and including means biasing said clamping means and said piston toward said outlet valve engaging means.
 8. The fitting as defined in claim 6 and in which said clamping means includes an arm member carried by said body and including a crossmember spaced from the inlet end of said piston and operative upon fluid being directed to the end of said piston opposite said inlet end to move relative to said piston toward a position engaging the side of said outlet valve opposite said inlet end of said piston to clamp said device to said container.
 9. The fitting as defined in claim 6 and including a pressure-regulating means connected to said outlet end of said piston.
 10. The fitting as defined in claim 9 and including a second device having a body, a piston axially slidably mounted within said body, clamping means movable relative to said piston and operable at one relative position of said piston and said clamping means to clampingly engage the outlet valve of a second container of pressurized fluid, said last-mentioned piston having inlet means received by said outlet valve and outlet means, and means connecting said outlet means and said pressure-regulating means.
 11. A clamping and fluid transmission fitting for connection to an outlet valve of a container of pressurized fluid, said valve comprising a stem extending from said container, and said fitting comprising: a body member including a closed loop portion and having a cylinder formed integral therewith; a piston reciprocably mounted in said cylinder provided with an inlet adapted at one position of said piston to communicate with said outlet valve of said container of pressurized fluid when said loop portion is engaged over said stem and at another position to disengage from said outlet valve, said closed loop portion having spaced substantially parallel arm members carried by said body member and including a straight crossmember spaced from the inlet end of said piston and extending between said arm members, said crossmember being operative upon movement of said piston toward said outlet valve engaging position to engage the opposite side of said stem of said outlet valve to clamp said device to said container; outlet means connected to said inlet and adapted for connection to means for receiving pressurized fluid from said container; filter means intermediate said inlet and said outlet means, means for selectively moving said piston between said positions including means normally biasing said piston and said loop portion toward said stem of said outlet valve for clamping engagement therewith and means for receiving fluid from said outlet valve upon communication between said inlet of said piston and said outlet valve directed to an area behind said piston to augment the biasing movement of said piston and said loop portion towards said clamping engagement around said stem, said last-mentioned means comprising a chamber formed on one side of said piston, a passage through said piston connecting said inlet on the inlet side of said filter means with said chamber.
 12. A clamping and fluid transmission fitting for connection to the outlet valves of a pair of containers of pressurized fluid, each of said valves compriSing a stem extending from one of said containers, and said fitting comprising a pair of clamps: each of said clamps comprising: a body member having a closed loop portion and a cylinder formed integral therewith; a piston reciprocably mounted in said cylinder provided with an inlet adapted at one position of said piston to communicate with the outlet valve of one of said containers of pressurized fluid when said loop portion is engaged over the stem of said outlet valve and at another position to disengage from said outlet valve; means for selectively moving said piston between said positions including means normally biasing said piston and said loop portion toward one of the stems of said outlet valves for clamping engagement therewith and means receiving fluid from said outlet valve upon communication between said inlet of said piston and said outlet valve and directing the fluid to an area behind said piston to augment the biasing movement of said piston and said loop portion towards said clamping engagement around said stem; outlet means connected to a fluid actuating device for receiving pressurized fluid from said container, a filter means intermediate said inlet and said outlet means and said directing means including a passage through said piston connecting said area behind said piston with the inlet side of said filter means.
 13. The fitting as defined in claim 12, wherein said connecting means includes a tubular extension extending between the outlet means of one of said clamps and said fluid actuating device, the outlet means of the other of said clamps being connected directly into said fluid actuating device. 